Carrier for fin stabilized projectiles



May 20, 1969 J. R. BIRD CARRIER FOR FIN STABILIZED PROJECTILES FiledMarch 16, 1954 ATTORNEYS CARRIER FOR FIN STABILIZED PROJECTILES John R.Bird, Belmont, Mass., assignor to the United States of America asrepresented by the Secretary of the Army Filed Mar. 16, 1954, Ser. No.416,729 Int. Cl. F42b 13/48, 9/16 U.S. Cl. 102-42 14 Claims Theinvention described herein may be manufactured and used by or for theGovernment for governmental purposes without the payment to me of anyroyalty thereon.

This invention relates to certain new and useful improvements in acanister cartridge for launching a closely integrated plurality offinned pointed shafts or missiles, the purpose being to provide acartridge having a great range of penetration for a given amount ofpropellant and which will concentrate the finned shafts or missiles andprevent them from unduly scattering at maximum ranges.

In the ordinary canister cartridge the projectiles begin to separatealmost instantaneously upon emergence from the muzzle of the gun andeach projectile is thereafter subject to individual air resistance whichretards the range thereof. Moreover, due to the turbulence of muzzleblast together with incomplete stabilization at that time, theprojectiles begin to scatter on emergence and as a result the spread atthe target may be so great as to result in an insufficient number of theprojectiles being effective on the target.

Accordingly, a primary object of the invention is the provision of ananti-personnel canister cartridge provided with a plurality of finnedshafts or missiles and carrier means which hold the missiles in apackage after emergence from the gun barrel until the relative wind hasacquired a steady state and each missile is fully stabilized.

A further object of the invention is the provision of a canistercartridge containing a plurality of finned shafts or missiles which areheld together in a group by a carrier which releases the missiles forindividual flight after the carrier clears the muzzle blast.

A still further object is to provide a missile of novel constructionwhich permits a closely integrated plurality of such missiles.

Another object is to provide a missile casing with novel means to aid inholding the missile carrier about the grouped missiles during theinitial portion of flight until the carrier base drops off.

Additional objects, advantages, and features of the invention reside inthe structure, arrangement, and combination of parts as may beunderstood from the following description and accompanying drawings,wherein:

FIGURE 1 is a longitudinal sectional view through a preferred form ofthe complete cartridge.

FIGURE 2 is a perspective view of a moditfied form of the assembledhalves of a missile carrier forming a component part of the invention.

FIGURE 3 is a cross sectional view of the cartridge with the missilesremoved, and taken along line 33 \of FIGURE 1.

FIGURES 4, and 6 are fragmentary sectional views of additional ormodified forms of the missile carrier.

Referring specifically to details shown in the drawings, there isillustrated in FIGURE 1 a cartridge shell 1, which mainly conforms tostructure generally in use, and may embody the heretofore familiarstamped metal head 2 and conventional primer 3. In the head there isfixed a tubular casing or carrier 4 which may be composed of any wellknown material, such, for instance, as a fibrous composition likepasteboard or papier-mach. The forward end of the cartridge may beclosed by any conventional method,

3,444,813 Patented May 20, 1969 one of which is to cut in the end sectorshaped points 5 adapted to be turned inward to meet and form a flat endwall. A suitable charge of propellant 6 is arranged within the cartridgeimmediately forward of the primer. A wad 7 separates the explosive fromthe three piece missile carrier 8.

The missile carrier comprises two mating separate semicylindricalsections 9 and 10 and a disc-shaped separable base 11 positioned at therear end of the sections. The forward ends 12 and 13 of the matingsections are bent or crimpeid inwardly and reanwardly to extend asuflicient distance substantially as shown, to hold the missiles snuglytogether in a conical formation in a manner obvious from inspection ofFIGURE 1. The cylindrical portion of the carrier is so dimensioned as tobe of greater length than the missiles after completion and thus projectbeyond the end of the missile cluster, whereby the inturned portion isadapted to open the crimp of the casing 1 upon firing of the shell.

Each missile is a one-piece item and consists of a narrow elongatedshaft 14, of substantially constant diameter throughout, having apointed front end 15 and plurality of exterior longitudinally disposedfins 16 formed by stamping or pressing to extend from the rear end atright angles to each other. In the missiles shown there are fourequiangularly spaced fins. This particular shape of the missile not onlygives it an unusual range and effectiveness, owing to the reducedresistance to its passage through the air and through the body of thetarget, but it also causes it to assume and maintain an effectivehead-on position throughout its flight, keeps air resistance at aminimum and increases penetration at any given effective range.

Referring to the modified form of missile carrier shown in FIGURE 2, theforward end of the carrier 18 is provided with a narrow continuous bandor adhesive tape 19, this band or tape is partially split in two or moreplaces from its rearward edge forwardly, as indicated at a, FIGURE 2.The splits are equi-distantly spaced from each other.

Other modifications of the missile carrier are shown in FIGURES 4 and 5wherein the carrier base is shown modified. In FIGURE 4 there isdisclosed a base 21 having a peripheral rim 22 with an outwardly andforwardly extending taper as indicated at 22. The rear ends 23 and 24 0fthe missile carrier sections are reanwardly and inwardly tapered to fitwithin the tapered rim of the base whereby these ends are initially heldtogether. In FIGURE 5 the difference consists in that the periphery ofthe rear surface of the carrier base 31 is provided with a rearwardlyextending rim 32 adapted to be expanded against the gun barrel by gaspressure to :obturate against gas leakage. This configuration provides alight base portion with little momentum when fired since separateobturating wads or thick base portions may be eliminated.

Referring to the modification shown in FIGURE -6 the generalconfiguration of the missile carrier is the same as that shown in FIGURE1 except that the length of the semi-cylindrical sections 49 and 50 isless than that of the missiles resulting in the pointed end of themissiles tearing through the crimp ahead of the forward end of themissile carrier when the cartridge is fired. When a cartridge embodyingthe invention is fired the carrier containing the finned missiles isprojected forcing the sector shaped points of the crimped end of thecasing aside as they emerge. The carrier and the missiles travel throughthe air together during the initial portion of the flight. As thecarrier and its package of missiles emerges from the barrel the base 11,21 or 31 as the case may be, drops off, allowing air to flow through andbetween the grouped missiles effecting their stabilization. The twosemi-cylindrical halves of the carrier are then forced apart after whicheach of the missiles proceeds individually along generally paralleltrajectories to the target.

With prior art canister cartridges, the missiles emerge substantiallyindividually from the muzzle of the gun. At the instant of emergence,the velocity of the missiles is a maximum. But due to turbulence of themuzzle blast together with the fact that it takes an appreciable timeand distance after emergence for the air flow about the missiles tobecome steady and uniform, the missiles are unduly scattered. As aresult the missiles are usually too dispersed at the target range andtoo few of them are effective upon the target.

With my invention the missiles are retained in a cluster, group orpackage for an appreciable time after leaving the muzzle and for anappreciable distance therefrom. At this distance, the base of thecarrier has dropped oif, the air has begun to flow through the carrierhalves and over and about the missiles and, in fact, has reached asubstantially steady state. The carrier halves then separate and dropaway from the cluster. Thereafter each missile proceeds individuallyalong a trajectory generally parallel to the others; and since each hasbecome fully stabilized by the relative wind, dispersion is reduced anda more concentrated pattern of hits on the target is effected.

It is therefore desirable and one of the principal objects of theinvention to delay separation of the carrier halves from the groupedmissiles until the base or wad has dropped off and thereafter until theair flow over and along the missiles has acquired a steady state. Themodifications of FIGURES 2, 4 and 5 present means for delaying the timeof opening of the cylindrical portion of the carrier. In order toprevent the front end of the carrier from opening prematurely, a band ortape 19 is provided, as shown in FIGURE 2. It has sufficient strength intension to withstand internal air pressure until the rear of thesections comprising the carrier are released by and separate from thebase 21 or 31. Thereafter the openmg of the rear of the carrier causesthe band or tape 19 to tear allowing the sections of the cylinder toseparate. This action is facilitated by slits 19a. The base shown inFIG- URES 4 and 5 is provided with the tapering rim 22 which engages thetapered portions 23 and 24 of the carrler and prevents the rear of thecarrier from opening until pressure of the propellant gas on the basehas substantially ceased. and the base has dropped olf. The carrierhalves then begin their separation along the rear portion of theircontacting edges. Increasing separation from rear to front results intearing of the band 19 at slits 19a and separation of the carrier fromthe cluster, in the manner previously explained. In FIGURE 5, therearward flange 32 on base 31 provides for an increased propellentcharge, reduces the mass of the parts which must be accelerated,improves obturation of propellent gases and therefore increases muzzlevelocity and affords greater range for the missiles. In all cases themissiles are retained in grouped or packaged relation until each isfully stabilized by the relative wind and as a result, flies a true pathWithout excessive dispersion.

1. A canister cartridge comprising a casing having a closed rear end, abase fitting said casing to confine a propellent charge in said rearend, first and second discrete semi-cylindrical sections fitting saidcasing and abutting said base, a frusto-conical shaped cluster of finnedmissiles fitting within the chamber jointly formed by said sections,said sections having inwardly thickened portions jointly defining aninternal circumferential band encircling and confining said missilesforwardly of the fins thereof to form said frustoconical cluster.

2. A canister cartridge as defined in claim 1, said casing being closedat the forward end and the front end of said sections extending beyondthe forward end of said missiles, whereby said carrier opens the closedfront end of said casing ahead of said missiles on firing the cartridge.

3. A canister cartridge as defined in claim 1, wherein the forward endsof said missiles extend beyond the front end of said sections, wherebythe forward ends of said missiles pass through the closed end of saidcasing before said sections.

4. A canister-type cartridge comprising a casing, a circular basefitting within said casing, a pair of semi-cylindrical separable matingsections fitting said casing and conjointly with said base, forming amissile carrier, a plurality of finned missiles forming a generallyfrusto-conical cluster having its rearward end fitting said carrier andin contact with said base, and peripheral thickened portions fixed withsaid sections internally thereof and conjointly defining band meansencircling and confining said cluster forwardly of the fins thereof.

5. A canister-type cartridge as recited in claim 4, said sections beingcrimped inwardly and rearwardly to form said thickened portions.

6. A canister-type cartridge as recited in claim 5, the forward ends ofsaid sections lying in a transverse plane forwardly of the forwardpointed ends of said missiles, whereby said sections open the crimpedforward end of said casing on firing of the cartridge.

7. A canister-type cartridge comprising a casing, a missile carrierfitting within said casing and including a base and two matingsemi-cylindrical discrete sections abutting the forward face of saidbase, said sections being crimped inwardly and rearwardly to define aninternally thickened forward end of said sections, and a frusto-conicalshaped cluster of finned missiles confined by said thickened end withinthe chamber conjointly formed by said sections.

8. A canister cartridge comprising a casing containing an explosivetherein, a split cylindrical carrier in said casing and separabletherefrom, said carrier having a separable base at its rear end and aninternally thickened open front end, and a closely integrated pluralityof finned shafts having pointed front ends, said shafts being positionedin said carrier with their longitudinal axes inclined inwardly at anangle with respect to the central longitudinal axis of said casing, saidintern-ally thickened front end grouping said shafts together at saidangle.

9. In a carrier for a canister-type cartridge, a circular base, a pairof semi-cylindrical mating sections resting on said base at their rearends, a generally frusto-conical cluster of finned missiles fittingwithin said sections with their finned ends against said base, theforward ends of said sections being internally thickened to contact theperiphery of said cluster between the tips and fins thereof to confinesaid cluster during an initial portion of the trajectory and releasesaid missiles inclined inwardly at an angle to the direction of flight.

10. A carrier as recited in claim 9, said base having a forwardlyextending rim internally tapered, said sections having their rearwardedges complementarily tapered, 't-o fit within said rim wherebyseparation of said sections during firing, is retarded.

11. A carrier as recited in claim 10, and a band encircling andconfining said sections at the forward ends thereof, said band beingpartially split from its rear edge forwardly in substantial coincidencewith the separable edges of said sections.

12. A carrier for the missiles of a canister-type cartridge comprising,a circular base, first and second semicylindrical separable matingsections having their rearward ends contacting said base, a generallyfrust-o-conical cluster of contacting finned missiles confined withinthe chamber conjointly defined by said sections, said missiles havingtheir forward ends rearwardly of the forward end of said sections, eachsaid section having an inwardlythickened circumferential portionperipherally contacting and confining said cluster between the endsthereof and forwardly of the finned ends thereof.

13. A carrier for the missiles of a canister-type cartridge comprising,a circular base, first and second semicylindrical separable matingsections resting on said base,

a generally frusto-conical cluster of finned projectiles confined by andWithin said sections with their finned ends contacting said base, saidsections being crimped rearwardly and inwardly to define a thickenedforward rim portion contacting and confining said cluster between theends thereof to form said frusto-conical cluster.

14. In a canister cartridge a missile carrier comprising a pair ofsemi-cylindrical separable mating sections having an open forward endand a separable base closing the rearward end, said open end beingcircumferentially internally thickened, a plurality of finned missilescontained within said carrier and held with their longitudinal axesinclined inwardly at an angle to the longitudinal axis of said carrierby said thickened end, and having their finned ends resting against saidbase, a frangible band means secured about said sections to hold thesame in References Cited UNITED STATES PATENTS 2/1879 Barnard 1U2--428/1916 Sheriff "102-42 V. R. PENDEGRASS. Primary Examiner.

US. Cl. X.R.

1. A CANISTER CARTRIDGE COMPRISING A CASING HAVING A CLOSED REAR END, ABASE FITTING SAID CASING TO CONFINE A PROPELLENT CHARGE IN SAID REAREND, FIRST AND SECOND DISCRETE SEMI-CYLINDRICAL SECTIONS FITTING SAIDCASING AND ABUTTING SAID BASE, A FRUSTO-CONICAL SHAPED CLUSTER OF FINNEDMISSILES FITTING WITHIN THE CHAMBER JOINTLY FORMED BY SAID SECTIONS,SAID SECTIONS HAVING INWARDLY THICKENED PORTIONS JOINTLY DEFINING ANINTERNAL CIRCUMFERENTIAL BAND ENCIRCLING AND CONFINING SAID MISSILESFORWARDLY OF THE FINS THEREOF TO FORM SAID FRUSTO-CONICAL CLUSTER.